harmony-commits mailing list archives

Site index · List index
Message view « Date » · « Thread »
Top « Date » · « Thread »
From "Dmitry Pronichkin (JIRA)" <j...@apache.org>
Subject [jira] Commented: (HARMONY-5597) [drlvm][jit][opt] Branch Translator zero comparison improvement
Date Fri, 21 Mar 2008 12:23:24 GMT

    [ https://issues.apache.org/jira/browse/HARMONY-5597?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=12581070#action_12581070

Dmitry Pronichkin commented on HARMONY-5597:

Egor, these operations are bitwise. Maybe you didn't catch _signed_ shift here? It spreads
sign bit for the whole value creating a mask for consequent operations.
That is absolutely similar idea to recently committed HARMONY-5580, just generalization.


> [drlvm][jit][opt] Branch Translator zero comparison improvement
> ---------------------------------------------------------------
>                 Key: HARMONY-5597
>                 URL: https://issues.apache.org/jira/browse/HARMONY-5597
>             Project: Harmony
>          Issue Type: Improvement
>            Reporter: George Timoshenko
>            Assignee: Mikhail Fursov
>            Priority: Minor
> In the implementation of branch translator enhancement (HARMONY-5580)
> prevInst - can be lookuped more carefully than just:
> Inst * prevInst = inst->getPrevInst();
> +
> +                    if (prevInst && falseInst)
> There can be some insts that do not affect FALGS between CMP and BRANCH.
> And it is also correct when CMP belongs to another BB that is prior to the BRANCH's one.
(the only restriction is: FLAGS are safe from CMP to BRANCH)

This message is automatically generated by JIRA.
You can reply to this email to add a comment to the issue online.

View raw message